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Q93045: DSWAP Increases by 16 Bytes Each Time an MS-DOS Program Is Run

Article: Q93045
Product(s): Microsoft Windows 95.x Retail Product
Version(s): WINDOWS:3.1,3.11
Operating System(s): 
Keyword(s): 
Last Modified: 12-DEC-1999

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The information in this article applies to:

- Microsoft Windows versions 3.1, 3.11 
- Microsoft Windows for Workgroups versions 3.1, 3.11 
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Each time you run an MS-DOS-based application in standard mode of
either Windows or Windows for Workgroups, the size of DSWAP.EXE in
memory increases by 16 bytes. This guarantees that each MS-DOS session
starts at a unique address.

MS-DOS keeps track of per-process information such as open files using
the address of the program segment prefix. If the size of DSWAP did
not increase, two MS-DOS-based applications could be started with the
same program segment prefix, and the system would have difficulty
distinguishing between them.

Additional query words: 3.10

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Keywords          :  
Technology        : kbAudDeveloper kbWin3xSearch kbWFWSearch kbZNotKeyword3 kbWin310 kbWin311 kbWFW310 kbWFW311
Version           : WINDOWS:3.1,3.11

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